Hi, My computer has 2 NIC with different IP addresses and subnets. The first NIC (192.168.0.150/24) is connected to the Internet through a gateway (192.168.0.1), and the second (192.168.2.3/24) is only connected to a closed network. When I try to contact an IP address that belongs to the subnet of the second NIC (192.168.2.21 for example), Windows first send ARP requests through the 2nd NIC, but if the requests fail, it sends the traffic to the default gateway through the 1st NIC. For example: >ping 192.168.2.21 Pinging 192.168.2.21 with 32 bytes of data: Reply from 192.168.2.3: Destination host unreachable. Reply from 192.168.0.1: Destination host unreachable. Reply from 192.168.0.1: Destination host unreachable. Reply from 192.168.0.1: Destination host unreachable. Ping statistics for 192.168.2.21: Packets: Sent = 4, Received = 4, Lost = 0 (0% loss), See, the first and second ping requests aren't sent using the same route. And once Windows has chosen to route those packets to the default gateway, it won't stop using it until the route isn't used for a period of time, no matter if the host becomes reachable again on the 2nd link. Is there a way to change this behavior, so that traffic for local subnets is never sent to the default gateway ? I tried adding static routes and static ARP entries to force Windows to always send traffic for 192.168.2.21 using the 2nd NIC, but it didn't work. Windows XP doesn't route packets that way, and it seems that behavior has been introduced with Windows Vista (someone already complained about that on the Vista forum, but no solution has been provided. I post my message in the Win7 forum in the hope a solution exists for Win7).

hi, it looks like relate to strong and weak host models. for more information, please read the article below. Strong and Weak Host Models http://technet.microsoft.com/en-us/magazine/2007.09.cableguy.aspx

Thanks for your help. I switched from the strong model to the weak model, but unfortunately, it didn't change the behavior I described.

Windows is not the same as Linux for multiple subnets. In brief Windows uses both ports to increase bandwidth. Linux on the other hand is more like a router. Windows Server can be granched that way but that is not easy either. Windows MVP, paid Remote Assistance is available for XP, Vista and Windows 7. My page on Video Card Problems is now my most popular landing page. See my gaming site for game reviews etc. Developer | Windows IT | Chess | Economics | Hardcore Games | Vegan Advocate | PC Reviews

hi, based on my experience and knowledge, the issue should be cause by the strong model. so would you mind confirm if you run the correct command for each NIC? for example: the correct command should be netsh interface ipv4 set interface "local area connection" weakhostsend=enabled netsh interface ipv4 set interface "local area connection" weakhostreceive=enabled netsh interface ipv4 set interface "local area connection 2" weakhostsend=enabled netsh interface ipv4 set interface "local area connection 2" weakhostreceive=enabled